Part Number: MB4556SX (King Bearing)
I am going to start with the mains because it's what I'm working on at the moment. Mopar does not sell these anymore (even though many sites are still listing them as available). They use a color-coding method for specifying bearings which is more common with newer vehicles, but was totally new to me. To make matters worse, there are no specific tolerances called out, but rather a tolerance stack is developed by using the specified combination of bearing colors (top and bottom can be different colors). The bearing codes are stamped to the front of the block, and the front crank counterweight.
All this said, there is a way to decrypt the Mopar specification table, and after backward-calculating their data, I ended up with a range of 0.0024"-0.0039" for the mains. I'm hoping to validate this through feedback from others as well as my own hands on experience with the engine I'm working on.
I ordered mains from Summit racing at a reasonable price ($103), and received them today. Here are the factory and King bearings side by side (factory is the darker one):
I went ahead and took some shell thickness measurements and found the King bearing to be ever so slightly thinner (King bearing averages 0.0796" vs factory 0.0799").
Next, I put the new bearings in the engine with plastigage. I'd like to describe the procedure i used to see if anyone has any objections to it:
I'm used to engines with individual main caps, and always measure the mains one at a time. However, in the case of the ecodiesel, the bedplate has 29 bolts holding it together with a LOT of pressure. I decided to just put the plastigage on each of the mains and measure them all at once. The other "deviation" from what might otherwise be recommended is that I used the old main bolts (which are torque-to-yield), and tightened everything down per the spec. One could argue that this may result in a false reading, but what I found leads me to believe it is OK. I will
be using new bolts for final assembly. After taking everything back apart, here are the measurements front to rear:
#1 Main: 0.0020"
#2 Main: 0.0015-0.0020" (was in between marks on the plastigage scale)
#3 Main: 0.0020"
#4 Main: 0.0020"
This is at the tighter end of the range I had calculated, however
I am rationalizing that the RTV in-between the bedplate and block has to be at least 0.0005" thick.
That's it for now. I'll add more as time permits